Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!caen!ox.com!fmsrl7!wreck From: wreck@fmsrl7.UUCP (Ron Carter) Newsgroups: sci.space Subject: Re: Excavating (minig) gold in Summary: Returning things is easy. Message-ID: <43884@fmsrl7.UUCP> Date: 17 Jun 91 19:56:26 GMT References: Reply-To: wreck@fmsrl7.UUCP (Ron Carter) Organization: Ford Motor Company, Scientific Research Labs, Dearborn, MI Lines: 23 In article dingbat@cix.compulink.co.uk (Codesmiths) writes: >I can't imagine any way of safely bringing a whole asteroid to the >earth's surface for a long, long time. Even if it was brought down in >small pieces it would still be several orders of magnitude beyond >present technology. Not true, if you're willing to sacrifice part of it. Just mold pieces into lens-shapes like an Apollo heat shield, and drop them. If they are mostly iron and land in water, you can just troll for them with an electromagnet to recover them. >What would be needed to smelt the asteroid in situ, and just bring >back the most valuable metals ? Good question, but separating the metals from the slag, the iron from the nickel, etc. has more possibilities than just returning unmodified asteroid pieces. If mirrors can be deposited using CVD, then it should be possible to make solar sails from iron. Attaching a sail and a small guidance module to a payload package (platinum and gold wrapped in slag or nickel) would allow them to sail back to Earth by themselves.